Combing through a child’s wet hair may lead to more accurate identification of active head lice infestation than visual inspection, according to a report in the March issue of Archives of Dermatology. However, visual inspection may yield a more precise assessment of the number of children who have eggs or nits (larvae) in their hair.
Head lice infestation (pediculosis capitis) is one of the most common childhood infections, affecting between 1 percent and 3 percent of 6- to 12-year-olds in industrialized nations, according to background information in the article. “In view of the high frequency of the infestation and the importance attributed to this parasitic skin disease by caregivers, governesses, teachers and healthcare providers, it comes as a surprise that the diagnostic accuracy of the techniques currently in use—visual inspection and wet combing—has never been determined appropriately,” the authors write. Health care professionals and lay personnel frequently overdiagnose head lice infestation and fail to distinguish between active and extinct cases.
Claudia Jahnke, MD, of the City Health Department in Braunschweig, Germany, and colleagues compared the two diagnostic methods in 304 students age 6 to 12 attending five German primary schools with head lice epidemics in 2007. Every child attending the schools was examined first by visual inspection, where an applicator stick was used to part the hair at the temples, behind the ears and on the neck. A second investigator, who did not know the results of the inspection, then applied a conditioner to wet the hair and combed from roots to ends with a fine-toothed comb. The conditioner was wiped on white sanitary paper and any object trapped within was examined with a magnifying glass.
Data from visual inspection were available for 304 children and from wet combing for 300 children. The presence of eggs or nits was detected in 79 children (26.3 percent) and lice in trophic stages (adults or nymphs) were seen in 21 children (7 percent).
“Visual inspection underestimated the true prevalence of active infestation by a factor of 3.5,” the authors write. Wet combing had a significantly higher sensitivity for detecting active infestations, correctly identifying them in 90.5 percent of the children (vs. 28.6 percent for visual inspections). However, visual inspection had a higher sensitivity for the identification of historic infestations (86.1 percent vs. 68.4 percent).
“In contrast to settings in the developing world in which a high intensity of infestation is the rule, in industrialized countries most children carry only a few lice,” the authors write. “In consequence, the optimal detection method should identify even a single louse and should have a high negative predictive value to exclude the possibility that individuals classified as negative for lice are actually false negative with the potential to spread the parasite. In this regard, wet combing is the only useful method if active infestation has to be ruled out.”
“Because visual inspection is rapidly performed, requires no additional resources other than a reusable applicator stick and is more sensitive, this technique is the method of choice if the frequency of historic pediculosis capitis is to be determined,” they conclude.
Reference: Arch Dermatol. 2009;145[3]:309-313.
Dear Helpdesk: Working in a Toxic Health Care Environment
March 28th 2024Dear Helpdesk is your steadfast companion, offering life coaching and workplace advice from 2 seasoned IPs for some of your most challenging real-life situations. Let us help you navigate the intersection between work and life, guiding you to navigate the dynamic world of infection prevention with confidence and grace. This article is on handling a toxic health care environment.
Product Locator: Spring and Early Mother's Day Gift Guide for Infection Prevention Personnel
March 27th 2024Whether it's a spring holiday, birthdays, or no reason at all, infection prevention personnel love to give and receive gifts that help at the end of a stressful day. Infection Control Today® offers some gift ideas for infection prevention personnel and their families.
Catching Up With Vangie Dennis, AORN 2022-2023 President at AORN 2024
March 26th 2024Infection Control Today (ICT) had the privilege of catching up with Vangie Dennis, MSN, RN, CNOR, CMLSO, at the Association of periOperative Registered Nurses' (AORN’s) International Surgical Conference & Expo 2024. As the former president of AORN and an esteemed figure in perioperative services, Vangie Dennis shared insights into her recent endeavors and the exciting new chapter she's embarked upon.
How To Optimize Your Time Management Strategies for the Busy Infection Preventionist
March 25th 2024Is your calendar resembling a chaotic masterpiece of overlapping tasks? Join the club of infection preventionists striving to balance responsibilities. Dive into proven strategies from a fellow infection preventionist to reclaim control of your time, streamline tasks, and boost productivity effectively. This is an IP Lifeline article.